Publications by Frédéric Courbin

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Strong gravitational lenses with measured time delays between the multiple images and models of the lens mass distribution allow a one-step determination of the time-delay distance, and thus a measure of cosmological parameters. We present a blind analysis ...

We report the discovery and spectroscopic confirmation of the quad-like lensed quasar system DES J0408-5354 found in the Dark Energy Survey (DES) Year 1 (Y1) data. This system was discovered during a search for DES Y1 strong lensing systems using a method ...

Simulations of self-interacting dark matter predict that dark matter should lag behind galaxies during a collision. If the interaction is mediated by a high-mass force carrier, the distribution of dark matter can also develop asymmetric dark matter tails. ...

We present a search for galaxy-scale strong gravitational lenses in the initial 2500 square degrees of the Canada-France Imaging Survey (CFIS). We designed a convolutional neural network (CNN) committee that we applied to a selection of 2 344 002 r-band im ...

We present a two-channel deconvolution method that decomposes images into a parametric point-source channel and a pixelized extended-source channel. Based on the central idea of the deconvolution algorithm proposed by Magain et al. (1998, ApJ, 494, 472), t ...

The ability to measure unbiased weak-lensing (WL) masses is a key ingredient to exploit galaxy clusters as a competitive cosmological probe with the ESA Euclid survey or future missions. We investigate the level of accuracy and precision of cluster masses ...

The Euclid Space Telescope will provide deep imaging at optical and near-infrared wavelengths, along with slitless near-infrared spectroscopy, across similar to 15 000deg(2) of the sky. Euclid is expected to detect similar to 12 billion astronomical source ...

We present a sample of 12 quasi-stellar objects (QSOs) that potentially act as strong gravitational lenses on background emission line galaxies (ELG) or Lyman-alpha emitters (LAEs) selected through a systematic search of the 297 301 QSOs in the Sloan Digit ...

Aims. We investigate the importance of lensing magnification for estimates of galaxy clustering and its cross-correlation with shear for the photometric sample of Euclid. Using updated specifications, we study the impact of lensing magnification on the con ...

The empirical correlation between the mass of a supermassive black hole (M-BH) and its host galaxy properties is widely considered to be an evidence of their co-evolution. A powerful way to test the co-evolution scenario and learn about the feedback proces ...

We compared the total mass density profiles of three different types of galaxies using weak gravitational lensing: (i) 29 galaxies that host quasars at (z) over bar similar to 0.32 that are in a post-starburst quasar (PSQ) phase with high star formation in ...

We present the results of a continuing survey to detect Ly alpha emitting galaxies at redshifts z similar to 9: the z equals nine' (ZEN) survey. We have obtained deep VLT Infrared Spectrometer and Array Camera observations in the narrow J-band filter NB119 ...

The Euclid mission will measure cosmological parameters with unprecedented precision. To distinguish between cosmological models, it is essential to generate realistic mock observables from cosmological simulations that were run in both the standard Lambda ...

We present the results of a visual search for galaxy-scale gravitational lenses in similar to 7 deg(2) of Hubble Space Telescope (HST) images. The data set comprises the whole imaging data ever taken with the Advanced Camera for Surveys (ACS) in the filter ...

Context. The Copernican principle, the notion that we are not at a special location in the Universe, is one of the cornerstones of modern cosmology. Its violation would invalidate the Friedmann-Lemaitre-Robertson-Walker metric, causing a major change in ou ...

Aims. We derived galaxy colour selections from Euclid and ground-based photometry, aiming to accurately define background galaxy samples in cluster weak-lensing analyses. These selections have been implemented in the Euclid data analysis pipelines for gala ...

A rare case of a quasar acting as a gravitational lens allows a precise determination of the mass of the quasar's host galaxy and offers a new path to studying the connections between supermassive black holes and their host galaxies. ...

Strong gravitational lens systems with time delays between the multiple images allow measurements of time-delay distances, which are primarily sensitive to the Hubble constant that is key to probing dark energy, neutrino physics and the spatial curvature o ...

Euclid will be the first space mission to survey most of the extragalactic sky in the 0.95-2.02 mu m range, to a 5 sigma point-source median depth of 24.4 AB mag. This unique photometric dataset will find wide use beyond Euclid's core science. In this pape ...

We demonstrate the potential of Euclid’s slitless spectroscopy to discover high-redshift (z > 5) quasars and their main photometric contaminant, ultracool dwarfs. Sensitive infrared spectroscopy from space is able to efficiently identify both population ...

Frédéric Courbin

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Two Accurate Time-Delay Distances From Strong Lensing: Implications For Cosmology

Discovery of the Lensed Quasar System DES J0408-5354

A test for skewed distributions of dark matter, and a possible detection in galaxy cluster Abell 3827

Strong lensing in UNIONS: Toward a pipeline from discovery to modeling

Firedec: a two-channel finite-resolution image deconvolution algorithm

Euclid preparation: LXV. Determining the weak lensing mass accuracy and precision for galaxy clusters

Euclid preparation XXII. Selection of quiescent galaxies from mock photometry using machine learning

Quasi-stellar objects acting as potential strong gravitational lenses in the SDSS-III BOSS survey

Euclid preparation XIX. Impact of magnification on photometric galaxy clustering

H0LiCOW. VI. Testing the fidelity of lensed quasar host galaxy reconstruction

A weak lensing comparability study of galaxy mergers that host AGNs

ZEN2: a narrow J-band search for z similar to 9 Ly alpha emitting galaxies directed towards three lensing clusters

euclid Preparation: Lxiii. Simulations and Non-linearities Beyond Lambda Cold Dark Matter. 2. Results From Non-standard Simulations

A 7 deg(2) survey for galaxy-scale gravitational lenses with the HST imaging archive(star)

Euclid: Testing the Copernican principle with next-generation surveys

Euclid preparation XXXVII. Galaxy colour selections with Euclid and ground photometry for cluster weak-lensing analyses

Strong gravitational lensing by AGNs as a probe of the quasar-host relations in the distant Universe

H0LiCOW-I. H-0 Lenses in COSMOGRAIL's Wellspring: program overview

Euclid preparation XVIII. The NISP photometric system

Euclid: The potential of slitless infrared spectroscopy: A z = 5.4 quasar and new ultracool dwarfs